Explanipedia

A Unified Maxwell–Bloch Framework for Multi-periodic 6.7 GHz Methanol Flaring in G9.62+0.20E Open

T. Rashidi, V. Anari, O. Powles, Gordon MacLeod, Yoshihiro Tanabe , et al. · 2025

We analyze a decade of 6.7 GHz methanol monitoring data in G9.62+0.20E, confirming the known periodicities of p1 = 241.3 ± 2.3 d and p2 = 52.5 ± 0.3 d, and identifying three new cycles at p3 = 127.0 ± 1.6 d, p4 = 163.9 ± 2.9 d, and p5 = 20…

Relativistic Maxwell-Bloch Equations with Applications to Astrophysics Open

Nicholas X. Fang, Martin Houde, Fereshteh Rajabi · 2025

We derive relativistic Maxwell-Bloch equations for potential applications in astronomical environments, where various radiative processes are known to occur, including the maser action and Dicke's superradiance. We show that for both pheno…

Spectro-temporal analysis of ultra-fast radio bursts using per-channel arrival times Open

Mohammed A Chamma, Victor Pop, Fereshteh Rajabi · 2025

Fast radio bursts (FRBs), especially those from repeating sources, exhibit a rich variety of morphologies in their dynamic spectra (or waterfalls). Characterizing these morphologies and spectro-temporal properties is a key strategy in inve…

Modelling the Periodic 6.7 GHz Methanol Flaring in G22.356+0.066 Open

T. Rashidi, V. Anari, A. Bartkiewicz, P. Wolak, M. Szymczak , et al. · 2025

We present a comprehensive analysis of the periodic flares observed in the 6.7 GHz methanol transition in G22.356+0.066, utilizing the Maxwell–Bloch equations (MBEs) as a framework to model these phenomena. By solving the one-dimensional M…

Quantum coherence and the invisible Universe: Subradiance as a dark matter mechanism Open

Martin Houde, Fereshteh Rajabi · 2024

We investigate the role of quantum entanglement and coherence in suppressing radiation and explore its implications for dark matter. Using Dicke's framework, we demonstrate that entangled states in a gas at thermal equilibrium can lead to …

Spectro-temporal analysis of ultra-fast radio bursts using per-channel arrival times Open

Mohammed A Chamma, Victor Pop, Fereshteh Rajabi · 2024

Fast radio bursts (FRBs), especially those from repeating sources, exhibit a rich variety of morphologies in their dynamic spectra (or waterfalls). Characterizing these morphologies and spectro-temporal properties is a key strategy in inve…

Impact of propagation effects on the spectro-temporal properties of Fast Radio Bursts Open

Aishwarya Kumar, Fereshteh Rajabi, Martin Houde · 2024

We present a mathematical analysis of propagation-induced distortions in the spectro-temporal properties of Fast Radio Bursts (FRBs). Within the Triggered Relativistic Dynamical Model, we derive a centroid-based formulation of the sub-burs…

Superradiance and Periodic 6.7 GHz Methanol Flaring in G22.356+0.066 Open

T. Rashidi, V. Anari, A. Bartkiewicz, P. Wolak, M. Szymczak , et al. · 2024

We present a comprehensive analysis of the periodic flares observed in the 6.7 GHz methanol transition in G22.356+0.066, utilizing the Maxwell-Bloch equations (MBEs) as a framework to model these phenomena. By solving the one-dimensional M…

Validating the sub-burst slope law: a comprehensive multisource spectro-temporal analysis of repeating fast radio bursts Open

K. B. Brown, Mohammed A Chamma, Fereshteh Rajabi, Aishwarya Kumar, Hosein Rajabi , et al. · 2023

We conduct a comprehensive spectro-temporal analysis of repeating fast radio bursts (FRBs) utilizing nine distinct sources, the largest sample to date. Our data set includes 175 sub-bursts and 31 multicomponent bursts from 11 data sets, wi…

Validating the Sub-Burst Slope Law: A Comprehensive Multi-Source Spectro-Temporal Analysis of Repeating Fast Radio Bursts Open

K. B. Brown, Mohammed A Chamma, Fereshteh Rajabi, Aishwarya Kumar, Hosein Rajabi , et al. · 2023

We conduct a comprehensive spectro-temporal analysis of repeating Fast Radio Bursts (FRBs) utilizing nine distinct sources, the largest sample to date. Our data set includes 175 sub-bursts and 31 multi-component bursts from 11 data sets, w…

Investigations of 2D ion crystals in a hybrid optical cavity trap for quantum information processing Open

Zewen Sun, Yi Hong Teoh, Fereshteh Rajabi, Rajibul Islam · 2023

We numerically investigate a hybrid trapping architecture for 2D ion crystals using static electrode voltages and optical cavity fields for in-plane and out-of-plane confinements, respectively. By studying the stability of 2D crystals agai…

Variability, flaring and coherence -- the complementarity of the maser and superradiance regimes Open

Martin Houde, Fereshteh Rajabi, Gordon MacLeod, S. Goedhart, Yoshihiro Tanabe , et al. · 2023

We discuss the role that coherence phenomena can have on the intensity variability of spectral lines associated with maser radiation. We do so by introducing the fundamental cooperative radiation phenomenon of (Dicke's) superradiance and d…

A broad survey of spectro-temporal properties from FRB 20121102A Open

Mohammed A Chamma, Fereshteh Rajabi, Aishwarya Kumar, Martin Houde · 2023

We survey the spectro-temporal properties of fast radio bursts from FRB 20121102A observed by earlier studies across a wide range of frequencies. We investigate 167 bursts from FRB 20121102A spanning frequencies 1–7.5 GHz, durations of les…

Variability, flaring and coherence – the complementarity of the maser and superradiance regimes Open

Martin Houde, Fereshteh Rajabi, Gordon MacLeod, S. Goedhart, Yoshihiro Tanabe , et al. · 2022

We discuss the role that coherence phenomena can have on the intensity variability of spectral lines associated with maser radiation. We do so by introducing the fundamental cooperative radiation phenomenon of (Dicke’s) superradiance and d…

Super-radiance from a relativistic source Open

Christopher M. Wyenberg, Fereshteh Rajabi, Martin Houde · 2022

Cooperative super-radiant emission from a highly relativistic multi-particle source is modeled and solved for the simple case of two particles. An existing model of a single relativistic two-level particle is used to construct a Hamiltonia…

A broad survey of spectro-temporal properties from FRB 20121102A Open

Mohammed A Chamma, Fereshteh Rajabi, Aishwarya Kumar, Martin Houde · 2022

We survey the spectro-temporal properties of fast radio bursts from FRB 20121102A observed by earlier studies across a wide range of frequencies. We investigate 167 bursts from FRB 20121102A spanning frequencies 1--7.5GHz, durations of les…

Transient Structure in the Non-linear Superradiance Regime of Widely Doppler Broadened Media Open

Christopher Wyenberg, Fereshteh Rajabi, Mohammed Chamma, Aishwarya Kumar, Martin Houde · 2022

We investigate transient radiation processes in the non-linear superradiance (SR) regime of the Doppler broadened Maxwell-Bloch equations when the velocity distribution is of total bandwidth greatly exceeding that of the transient process …

Superradiance from a Relativistic Source Open

Christopher Wyenberg, Fereshteh Rajabi, Martin Houde · 2022

We construct a model of cooperative superradiant emission from a highly relativistic multi-particle source. We revise an existing model of the literature for a relativistic two-level particle, and construct from it a Hamiltonian describing…

The generation and transformation of polarization signals in molecular lines through collective anisotropic resonant scattering Open

Martin Houde, Boy Lankhaar, Fereshteh Rajabi, Mohammed A Chamma · 2021

We discuss the existence of elliptical polarization in rotational spectral lines of CO and other molecules within the context of the Anisotropic Resonant Scattering (ARS) model. We show that the effect of ARS on the radiation field can lea…

Manipulating phonons of a trapped-ion system using optical tweezers Open

Yi Hong Teoh, Manas Sajjan, Zewen Sun, Fereshteh Rajabi, Rajibul Islam · 2021

We propose an experimental architecture where an array of optical tweezers\naffords site-dependent control over the confining potential of a conventional\nradio-frequency ion trap. The site-dependent control enables programmable\nmanipulat…

Generalization of the Menegozzi and Lamb maser algorithm to the transient superradiance regime Open

Christopher M. Wyenberg, Boy Lankhaar, Fereshteh Rajabi, Mohammed A Chamma, Martin Houde · 2021

We investigate the application of the conventional quasi-steady state maser modelling algorithm of Menegozzi & Lamb (ML) to the high field transient regime of the one-dimensional Maxwell-Bloch (MB) equations for a velocity distribution of …

Evidence of a shared spectro-temporal law between sources of repeating fast radio bursts Open

Mohammed A Chamma, Fereshteh Rajabi, Christopher M. Wyenberg, Abhilash Mathews, Martin Houde · 2021

We study the spectro-temporal characteristics of two repeating fast radio bursts (FRBs), namely, FRB 20180916B and FRB 20180814A , and combine the results with those from our earlier analysis on FRB 20121102A. The relationship between the …

A shared law between sources of repeating fast radio bursts Open

Mohammed A Chamma, Fereshteh Rajabi, Christopher M. Wyenberg, Abhilash Mathews, Martin Houde · 2020

We study the spectro-temporal characteristics of two repeating fast radio bursts (FRBs), namely, FRB~180916.J0158+65 and FRB~180814.J0422+73, and combine the results with those from our earlier analysis on FRB~121102. The relationship betw…

A simple relationship for the spectro-temporal structure of bursts from FRB 121102 Open

Fereshteh Rajabi, Mohammed A Chamma, Christopher M. Wyenberg, Abhilash Mathews, Martin Houde · 2020

We consider a simple dynamical and relativistic model to explain the spectro-temporal structure often displayed by repeating fast radio bursts (FRBs). We show how this model can account for the downward frequency drift in a sequence of sub…

Astronomical masers and Dicke’s superradiance Open

Fereshteh Rajabi, Martin Houde · 2020

We consider the radiation properties and processes of a gas with a population inversion using the formalism based on the Maxwell–Bloch equations. We focus on the maser action and Dicke’s superradiance to establish their relationship in the…

Detection of new methanol maser transitions associated with G358.93−0.03 Open

Gordon MacLeod, Koichiro Sugiyama, T. R. Hunter, J. Quick, Willem A. Baan , et al. · 2019

We report the detection of new 12.178, 12.229, 20.347, and 23.121 GHz methanol masers in the massive star-forming region G358.93−0.03, which are flaring on similarly short time-scales (days) as the 6.668 GHz methanol masers also associated…

Monitoring Raman emission through state population in cold atoms confined inside a hollow-core fiber Open

Taehyun Yoon, Zhenghao Ding, Jeremy Flannery, Fereshteh Rajabi, Michal Bajcsy · 2019

We study the spontaneous Raman emission in an ensemble of laser-cooled three-level Λ-type atoms confined inside a hollow-core photonic-bandgap fiber using a novel approach to observe the process. Instead of detecting the emitted light, we …

Dynamical Hamiltonian engineering of 2D rectangular lattices in a one-dimensional ion chain Open

Fereshteh Rajabi, Sainath Motlakunta, Chung-You Shih, Nikhil Kotibhaskar, Qudsia Quraishi , et al. · 2019

Controlling the interaction graph between spins or qubits in a quantum simulator allows user-controlled tailoring of native interactions to achieve a target Hamiltonian. Engineering long-ranged phonon-mediated spin–spin interactions in a t…

New evidence for Dicke’s superradiance in the 6.7 GHz methanol spectral line in the interstellar medium Open

Fereshteh Rajabi, Martin Houde, A. Bartkiewicz, M. Olech, M. Szymczak , et al. · 2019

We present new evidence for superradiance in the methanol 6.7 GHz spectral\nline for three different star-forming regions: S255IR-NIRS3, G24.329+0.144, and\nCepheus A. Our analysis shows that some of the intensity flares exhibiting fast\nf…

Triggered superradiance and fast radio bursts Open

Martin Houde, Fereshteh Rajabi, B. M. Gaensler, Abhilash Mathews, Victor Tranchant · 2018

In this study, we develop a model for fast radio bursts (FRBs) based on triggered superradiance (SR) and apply it to previously published data of FRB 110220 and FRB 121102. We show how a young pulsar located at ~100 pc or more from an SR/F…

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